Ammunition articles typically are supersonic and generate an audible sound when the projectile travels at a speed greater than 1,100 feet per second during flight to the target (“supersonic articles”). This sound can be disadvantageous in military or covert operations because it may reveal the location where the supersonic article was discharged and ruin the element of surprise. Furthermore, noise can be an issue in law enforcement and commercial applications which needs to be abated.
Subsonic ammunition articles (“subsonic articles”) have been developed that do not produce the distinguishable audible sound associated with supersonic articles. Such articles typically have less muzzle flash, use oversized projectiles, use less powder volume and function in traditional gas operated weapons. The propellant charge usually is a small charge loaded in a large cavity or gun powder with a filler. Using a reduced propellant charge without sizing the cavity to the propellant charge leaves a partially filled cavity resulting in inconsistent propellant distribution, prohibits uniform ignition and significantly alters the burn profile. The reduced propellant charge may create lower pressures which makes consistent and complete case mouth obturation (“chamber sealing”) difficult and makes it hard to get a clean burn of the propellant causing rapid fouling of the weapon. In some cases, subsonic articles do not produce sufficient port pressure to enable subsonic articles to cycle properly in gas operated weapons.
The PCA articles and associated methods for making the same set forth herein address the above referenced disadvantages associated with conventional subsonic articles and methods. PCA articles presented herein generally have a thermal polymer based material (“polymer”) cartridge casing (“casing”) that holds a projectile in the first end (“neck”), and has a cavity and a base cap (“base cap”) attached to the casing second end. A subsonic PCA article may contain a core that is molded around a core pull containing a base cap, cavity sleeve, and a neck (“core sleeve” or “CS”).
It should be noted that articles contained herein are designed to function in existing weapons interchangeable with existing ammunition articles with functionality and performance improved over existing subsonic ammunition articles.